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Finding the Fourth Proportional to 662.70, 994.05 and 420.30

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Solution

The fourth proportional to 662.70, 994.05 and 420.30 is: 630.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    662.70 : 994.05 = 420.30 : x
  2. Step 2: Convert to fraction form
    662.70/994.05 = 420.30/x
  3. Step 3: Cross multiply
    662.70x = 994.05 × 420.30
  4. Step 4: Simplify right side
    662.70x = 417,799.22
  5. Step 5: Solve for x
    x = 417,799.22/662.70
  6. Step 6: Final answer
    x = 630.45

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.